Lifting-jack.



FPL. GORMLEY.

LIFTING JACK.

APPLICATION mm MAR. 23. ms.

1 ,2? 6,992. Patented Aug. 27, 191.8.

liwcnmr Frank l1. 602721333,

' 32 ispositioned a cam member 35 pivotally mounted on a pin 36 secured in the cars 32.

WVhen the cam member is in the position shown in Fig. 2 the key 28 will be locked in elevated position with its upper wall abutting the wall 37 at the upper end of the slot 31 and with its inner end projecting into the slot 27.

The cam member 35 is provided with a ring 38, or some similar member by which the said cam member may be pulled out from beneath the key 28, thereby permitting said key 28 to drop downwardly, and at the same time on account of the inclination of the slot '34 said key 28 will be moved outwardly.

Whenin this lowest position the inner end of the key 28 will be out of the path of the shoulder'30 and the ram 12 may be removed.

WVhen the ram 12 has been replaced the key 28 is raised to its normal elevated position and the cam member 35 is forced beneath it, thereby effectually looking it in operative position.

' ltflwillbe noted that in this construction of safety device for lifting jacks all the parts thereof are permanently attached to the jack and cannot be misplaced.

If the key 28 becomes worn or broken, said key may be removed by first forcing the pin 33 from the ears 32 in which its ends are positioned. l p A new key may then be posltioned 1n the slot 31, and the pin 33 inserted in the cars 32 I and through the inclined slot 34 and the jack will again'be ready for use.

I In like manner the pin 36 may be forced from its bearings in the ears 32 if it-i s desired to replace the cam member 35.

It is believed that the operation and many advantages of the invention will be thor oughly understood without further description.

Having thus described my invention, I claim c 7 1.'In a lifting jack, the combination of a cylinder,a ram therein provided with a ver tical peripheral slot with aclosed lower end; a key mounted in a slot insaidcylinder with its inner end normally extending'into said peripheral slot; and a movable member for locln'ng said key in its normal position, but

adapted tobe removed from the path of said key thereby permitting'said key to be moved outwardly from said slot.

2. In a lifting jack, the combination of a cylinder, having parallel vertical ears extending'therefr'om; a ram in said cylinder having a vertical peripheral slot with a closed lower end; a key interposed between said ears and normally extending through said cylinder into said slot; and means for locking said key in its iimer normal position and adapted to be removed from the path of said key therebypermitting said key to be moved outwardly from said slot.

3. In a lifting jack, the combination of a cylinder having parallel ears extending therefrom; a ram in said cylinder having a vertical peripheral slot with a closed lower end; a key interposed between said ears and extending through'fsaid cylinder into said slot, said key having an inclined slot extending therethrough; a pin mounted in said ears and extending through said slot; and means for normally retaining said key in operative position.

4. In a lifting jack, the combination of a cylinder, having parallel ears extending therefrom; a ram in said cylinder havinga vertical peripheral slot with a closed lower end; a'key interposed between said ears and extending through said cylinder into said slot, said key having an inclined slotextending therethrough; a pin mounted in said ears andextending'through said slot; and means acting on the-lower end of said key for normally retaining said key inoperative position. 5. In a lifting jack, the combination of a cylinder, having parallel ears extending therefrom; a ram in said cylinder having a vertical peripheral slot with a closed lower end; a key interposed between said ears and extending through said cylinder into said slot, said key having an inclinedslot extend- ,ing' therethrough; a pin mounted in said ears and extendingthrough said slot; and means pivoted to an ear and actingon the lower end of said keyfor normally retaining said key in operative positionu 6. In a lifting jack, the combination of a cylinder, having parallel ears extending therefrom; a ram in said cylinder having a vertical peripheral slot with a closed lower end; a key interposed between said ears and extending through said. cylinder into said slot, said key having a inclined slot extending therethrough; a pin mounted in said ears and extending through'saidslot; and a cam member pivotally mounted between said ears and adapted to retain said key in operative position.

7. In a lifting jack,"the combination'of a cylinder, having parallel ears extending therefrom; a ram in said cylinder-having a vertical peripheral slot with a closed lower end; a key interposedbetween said ears and extending through said cylinder into said ber may be removed from beneath said key.

8. In a lifting jack, the combination of a cylinder having a slot therethrough with its upper Wall perpendicular to the axis of said cylinder; a ram having a barrel portion in said cylinder, said barrel portion being of equal diameter throughout its length and having a vertical peripheral slot closed at theloWer end; a rectangular key in said cylinderslot; means for positively locking said key in said slot With its upper edge abutting the upper Wall of the cylinder slot and adapted to be actuated to permit said key to be moved outwardly free from the slot in said ram.

Signed by me at 4 Post Ofiice Square, Boston, Mass, this 21st day of March, 1918.

FRANK L. GORMLEY.

Witnesses: V

WALTER E. LOMBARD, NATHAN C. LOMBABD.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patent:,

Washington, D. 0. t 

